# Evaluation of a New Sublingual Methylcobalamin Dosage Regimen for Childhood Vitamin B12 Deficiency

## TL;DR

This study compares a new sublingual vitamin B12 treatment with injections in children and finds both are equally effective.

## Contribution

A new sublingual methylcobalamin dosing protocol for childhood vitamin B12 deficiency is evaluated and shown to be noninferior to intramuscular injections.

## Key findings

- Sublingual methylcobalamin increased vitamin B12 levels as effectively as intramuscular cyanocobalamin.
- Both treatment groups achieved statistically significant increases in serum B12 levels above 300 ng/L.
- The sublingual protocol was well-tolerated and noninvasive, making it a viable alternative to injections.

## Abstract

Background: Effective and timely treatment of vitamin B12 deficiency in childhood is crucial because it can lead to serious issues, including delayed growth and neuromotor development. Available treatment options include oral, intramuscular, and sublingual administration. Aim: This study investigated the efficacy of a new dosing protocol for sublingual methylcobalamin. Materials and Methods: In total, 312 patients with vitamin B12 deficiency (serum level < 250 ng/L) were divided into two groups based on their treatment type: intramuscular cyanocobalamin (Group 1) and sublingual methylcobalamin (Group 2). Group 1 included 29 (9.3%) patients, and Group 2 included 283 (90.7%) patients, with 56 (18%) patients in Group 2 undergoing treatment for childhood cancer. The sublingual methylcobalamin protocol consisted of 1 puff (500 μg) daily for children under 8 years of age and 2 puffs (1000 μg) daily for those 8 years and older, administered for 1.5 months and then three times weekly for an additional 1.5 months. Results: The mean ages in Groups 1 and 2 were 10.07 ± 6.05 years (range, 1–17 years) and 7.43 ± 5.86 years (range, 0.1–17 years), respectively. The female/male ratio was 19/10 in Group 1 and 145/138 in Group 2. The most common diagnoses were anemia (72, 22.9%), cancer (56, 18.0%), and hemangioma (40, 12.7%). The median serum levels of vitamin B12 in Group 1 were 177 ng/L before treatment, 447 ng/L after 1.5 months, and 321.5 ng/L after 3 months. In Group 2, the levels were 172 ng/L before treatment, 438 ng/L after 1.5 months, and 360 ng/L after 3 months. There were no significant between-group differences. Both groups showed a statistically significant increase in levels above 300 ng/L. Discussion: Sublingual methylcobalamin, a noninvasive treatment option, was as effective as intramuscular cyanocobalamin. This study is to compare the standard intramuscular protocol with a new dosing regimen for sublingual methylcobalamin. This study showed that it is also useful for children to hold the spray in their mouths for 1 min and avoid food intake for the next 15 min.